环氧沥青混合料钢桥面铺装复合结构试验研究

针对某钢箱梁桥大交通量、重车比例高和夏季高温的具体情况和特点,采用环氧沥青混合料为钢桥面铺装,开展以带钢板的环氧沥青混合复合梁为研究对象的一系列试验。其中拉拔试验为测试疲劳过程对钢桥面铺装黏结层的影响;60℃时超载40%和60%两种超载荷载的疲劳试验为测试最佳疲劳油石比所对应的环氧沥青混凝土铺装的高温抗超载疲劳性能;极限弯曲试验用于确定复合梁试件的极限承载力;变温度变荷载疲劳试验用于预测钢桥面环氧沥青混凝土铺装在设计使用年限内所表现的性能或铺装层的使用寿命。试验结果表明所设计的环氧沥青混凝土铺装具有较强的抗高温超载疲劳能力,同时对荷载是十分敏感的。该铺装结构在正常的使用条件下可以满足设计使用要求。     

E_1级麻屑板用脲醛树脂胶的研究

根据亚麻屑的胶接特性,从脲醛胶的固体含量、粘度、游离甲醛、耐水性、固化时间、施工胶液特性及经济效益等方面系统地研究了适合低甲醛释放量麻屑板生产用脲醛树脂胶的物理力学及化学性能。研究结果表明,使用改进的脲醛树脂胶(命名为DN—9号和DN—11号低毒腮醛胶)可以压制出甲醛释放量小于10mg/100g的E1级麻屑板,其物理力学性能达到GB 4896—4905—35标准     

SMA在铺筑路面中应注意的几个问题

叙述了SMA混合料的拌制、铺筑、碾压、接缝四个生产过程，并结合实际提出各过程中应注意的问题。     

Road paving,fire regime feedbacks,and the future of Amazon forests

Fire poses the greatest threat to the forests of Amazônia. The magnitude of this threat is amplified by three positive feedback loops that drive the expansion of forest fire in the region: (1) Fire promotes drought, and therefore more fire, by releasing smoke into the atmosphere, thus reducing rainfall. Fire-assisted conversion of forests to pastures may also promote drought by increasing albedo and decreasing water vapor flux to the atmosphere, further inhibiting rainfall. (2) Fire increases the susceptibility of forests to recurrent burning by killing trees, thereby allowing sunlight to penetrate the forest interior, and increasing the fuel load on the forest floor. (3) Finally, fires also self-perpetuate by burning agricultural and forestry systems, discouraging landholders from making those fire-sensitive investments in their land that would allow them to move beyond their dependence upon fire as a management tool.The long-term reduction of Amazon fire, and its substantial costs to society, is most likely to emerge through investments and policy change that stimulate permanent agricultural and forestry production systems within existing frontiers while slowing the rate of frontier expansion. But the Brazilian government’s plan to pave, recuperate or construct 6245 km of roads in the Amazon may have the opposite effect. We present research findings that the government plan would nearly double the area of forestland that is accessible by paved highways, including 192,000 km² of fire-prone forest. Our analysis finds that these roads will stimulate 120,000–270,000 km² of additional deforestation, and forest impoverishment through logging and understory fire, if the historical relationship between road paving and forest alteration by humans continues. Infrastructural investments are urgently needed in Amazônia to help integrate isolated urban centers into the market economy, to improve the quality of life for millions of rural Amazonians, and to improve the profitability of agribusiness in Brazil’s agricultural belt. But as currently planned, these investments will have the ancillary effects of accelerating deforestation, logging, forest fire, smoke-related illness, and the displacement of small-scale farmers.     

四川竹业区基地原料林的竹种选择与定向培育

根据四川竹产业发展规划和竹资源拓展实践，竹材制浆造纸和竹笋食品是发挥四川竹业综合比较优势的根本性产业。丛生竹及其资源拓展是进行纸浆、笋用原料林培育的首选模式。从区域基地的层面着重进行了竹种配置介绍，概述了丛生竹培育的关键技术。     

光皮桦优良遗传材料选择及改良前期效果

从形质指标、绝对生长量指标、相对生长量指标、木材材性指标4个方面制定了光皮桦选优标准,并确选优树28株。优树树高、胸径、木材密度、纤维含量、纤维长度分别大于林分平均值4．3％～45．9％、29．0％～81．7％、1．3％～10．3％、1．2％～10．1％、0．7％～9．6％。30个材料子代测定表明：优树子代不同的家系间,树高、胸径生长差异均达到极显著水平。经LSD显著性分析,评选出麻17、麻11、杨5、麻27、杨1、麻3、麻20、麻15共8个优良家系,可在生产中推广。     

一种新型竹木集成材粘着剂问世

CU—3型粘着剂为日本株式会社生产,日本竹协会特别推荐的具有超高水平,超高安全性能的水基乙烯聚氨酯型粘着剂。最适合于竹子集成材及各种木质集成材的粘合。作为竹材特选专用粘着剂,CU—3型粘着剂已经在日本国内广泛使用,并博得用户很高的评价。凡使用CU—3型粘着剂的竹木制品能够顺     

无公害粘虫胶防治枣树害虫试验研究

通过对枣树4种主要害虫进行无公害粘虫胶防治试验,发现对枣粉蚧、枣尺蛾和食芽象甲的防治效果达到90%以上,其中对枣树红蜘蛛的防治达99.5%以上,分别较对照提高了70%和75%以上。有效控制了枣红蜘蛛、枣粉蚧、食芽象甲和枣尺蛾的危害,平均每个粘虫胶环粘杀红蜘蛛1870头以上,粘杀枣粉蚧154头以上,食芽象甲4头以上,枣尺蛾5头以上,叶片被害率(包括有虫叶率)均控制在1%以下,达到了很好的防治效果。并且操作简便、节约用水、不造成环境和果品污染,有利于实现果品无公害生产。     

环境测试舱回收率测试方法的研究

采用液体标样注入、采样管先连续后间隔采样、自动热脱附仪(ATD)和气相色谱/质谱(GC/MS)联用分析、数据拟合积分计算等方法和技术,建立了挥发性有机化合物(VOCs)环境测试舱(简称VOCs舱)对8种VOCs(甲苯、乙烯基环己烯、对二甲苯、苯乙烯、2-乙基己醇、萘、4-苯基环己烯和正十二烷)的回收率测试方法。对比两台VOCs舱回收率的测试结果发现,对小分子化合物的回收率数据基本一致,均在83%~99%之间;但对大分子化合物的回收率数据存在明显差异,建议尽早开展制定VOCs舱回收率的测试标准。甲醛测试舱(简称甲醛舱)对8种VOCs的回收率测试结果远低于VOCs舱,尤其是萘和4-苯基环己烯,其回收率小于11%,建议在采用改造甲醛舱进行VOCs测试时多关注甲醛舱对于VOCs回收率的影响。     

征占用林地存在问题及对策

调查上高县征占用林地的现状,分析其存在的问题及其根源,并提出相应对策.